1. Field of the Invention
The present invention relates to a drive control system for an automobile and, more particularly, to a safety drive control system for an automobile which recognizes environmental circumstances so as to avoid obstructions.
2. Description of Related Art
Self-controlled driving cars are provided with an automatic drive control system which automatically recognizes environmental circumstances of a path ahead of the car so as to guide the car safely. An automatic drive control system, described in Japanese Unexamined Patent Publication No. 64-26913, includes a video camera for providing a stereo image based on which the car is automatically controlled so as to avoid a crash against an obstruction on the path ahead detected in the stereo image. The automatic drive control system can be conveniently used, even in cars driven by a driver. For instance, a car with an automatic cruise control feature has been on the market. Various drive control systems, such as an automatic steering control system and an automatic braking system, have been proposed to back up a driver's operation in order to automatically avoid car crashes.
However, conventional automatic drive control systems have a drawback in that they can not perform proper drive controls according to various drive situations. It is desired to control driving of a car with different algorithms for different drive situations, such as high speed driving, mountain trail driving, driving in heavy traffic, etc., and for different obstructions against which the car is expected to crash, such as guard rails on shoulders of a road, a preceding car on the path ahead, etc. The conventional automatic drive control system can not perform a control appropriate for various drive situations, so that it is difficult to take an emergency control for avoiding crashes.